Environment Canterbury spent more than $5 million on communicating with the public and within the organisation in the last financial year.
Data released under the Local Government Official Information and Meetings Act showed over the 2015-16 financial year, ECan spent $5,620,391 on its communications and external relations department.
The figure had jumped from $3,422,727 in the 2010-11 financial year.
ECan said that made up staff wages, communications advice, promotional design and production, printing and advertising, web development, photography and video, media monitoring, market research and behaviour change, and sponsorship and community events.
It also included operational expenses such as travel, phones, learning and development, and stationery.
On top of that, the figures show it spent $147,626 on external public relations, compared to $38,085 in 2010-2011.
That was for when "one-off" pieces of communication work were done by external contractors, or for when "specialist skills" were required.
ECan communications manager Tafflyn Bradford-James said during the 2015-16 financial year, there were 22.6 full-time equivalent staff.
They covered roles including web design, graphic design and print production, youth engagement, internal and external communications, media liaison, marketing and behaviour change campaigns, and industry and stakeholder engagement.
Nine of those were communications advisers.
Ms Bradford-James said as part of a restructure earlier this year, it now had an allocation of 25 FTE staff in the section.
She said at present, only 21 of those FTEs were filled.